Rotigotine is a Non-Dihydroergotoxine D3/D2/D1 dopamine receptor agonist, and long-term research shows that it has therapeutic effects on a variety of central nervous system diseases and mental disorders. As currently known, Rotigotine has superior effects in regard to the treatment or mitigation of Parkinson's disease, Restless Legs Syndrome, schizophrenia, depression and the like, and to the preventive treatment of Parkinson's disease (WO2005/063237). In particular, the therapeutic and mitigative effects of Rotigotine on Parkinson's disease are supported by substantive animal model studies and clinical tests (Neurology, Vol. 65 Suppl1: S3-S5/movement disorders Vol. 9 No. 2 P147-154; ARCH NEUROL, Vol. 60, December 2003: 1721-28). Rotigotine was first formulated into oral formulations, but was then found to exhibit an overly high clearance and a relatively short duration of action after oral intake. Thus, it could hardly achieve a therapeutically effective plasma concentration or be practically used owing to the need for frequent drug administration (Neurology, Vol. 65 Suppl1: S3-S5). Consequently, people tried to formulate Rotigotine into transdermal patches.
WO99/49852 describes a transdermal drug delivery system comprising Rotigotine on the basis of an acrylate or silicone. The adhesive used in this system is an acrylate or silicone, which independently of the other, forms a system involving a single adhesive together with the active drug. The system comprising an acrylate as adhesive has a low drug release rate; the system comprising a silicone as adhesive has a small drug load and a relatively low initial drug release rate.
WO2002/089778 describes the use of a silicone-based transdermal therapeutic system in the manufacture of an anti-Parkinson's disease medicament. This transdermal therapeutic system comprises Rotigotine as active ingredient. However, said system has a low drug release rate, and particularly requires too long a period of time to achieve an effective dosage. Consequently, there exist the following two problems: 1. the transdermal patch has to be changed frequently, for example once per 24 hours or shorter, to achieve an effective plasma concentration, and this is contrary to the advantage of convenient use of the patch by a patient; 2. the transdermal patch has a relatively low initial penetration level such that it takes too long a period of time for the drug to take effect after the application of the patch, usually resulting in the delay of the control of a patient's state of illness.
The inventors have thoroughly investigated the inherent disadvantages of the existing Rotigotine transdermal delivery systems. After a lot of tests, the inventors have found out that a matrix mixture system formed from a combination of an acrylic pressure-sensitive adhesive with a silicone pressure-sensitive adhesive, and polyvinylpyrrolidone which are present in a particular weight ratio is capable of sufficiently dissolving and releasing an effective amount of Rotigotine and of increasing the initial penetration level of Rotigotine. Thus, the Rotigotine releasing properties of the transdermal delivery system are improved. The present invention is hence finished.